Fluid-pressure engine-starter.



B. W. DAVENPORT. num PRESSURE ENGINE STARTER. A APPLICATION FILED .IULY 26. 1913. 1,189,067.

B. W. DAVENPORT.

FLUID PRESSURE ENGINE STARTER'. APPLICATION HLEu'luLY 26. 191s.

1,189,067. Ptent'd 31111927, 1916.

2 SHEETS-SHEET 2.

THE COLUMBIA PLANDGRAPH C0.. wASHlNnTN, IL C.

BIRGE W. DAVENPORT, OF MINNEAPOLIS, MINNESOTA.

FLUID-PRESSURE ENGINE-STARTER.

Specification of Letters Patent.

Patented June 27, 1916.

Application led July 26, 1913. Serial No. 781,446.

T0 all whom t may concern.'

Be it known that I, BIRGE WV. DAVENPORT, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Fluid- Pressure Engine-Starters; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention is a starter for internal combustion engines.

One object of the invention is to provide a simple, durable and eiiicient device for cranking the engine with but little physical exertion, the device operating to afford the preliminary revolutions necessary to give an explosive engine for the purpose of starting the same7 thereby preventing many serious accidents which result from cranking an engine by hand.

A further aim of the invention is to provide means whereby the device may be disconnected and the engine cranked byhand, when desired. Furthermore, the automatic cranking device is provided with means whereby the engine shaft will be revolved slowly at first, and thence the speed of the shaft gradually increased, thereby obtaining results which are considered essential to the successful starting of an engine.

The invention further contemplates the application of a clutch mechanism and the provision of means to actuate the starting mechanism by the movement of a single operating element, such as a foot lever.

lith these and other objects inview, the invention comprises a starting shaft positioned adjacent to an engine shaft and having clutch mechanism operating with both of said shafts. Means are employed for storing iiuid under pressure, such as compressed air, and a control valve is positioned between this storing means and a fluid actuated device for rotating the starter shaft. The action of this valve is governed by means under the Acontrol of the vehicle driver, which means also governs the movement of the clutch mechanism.V A variable drum is carried by the starter shaft, and means are employed for connecting the fluid actuated device with the drum for imparting a gradual 'slow movement to the engine shaft and thence a relatively faster movement thereto. Mea-ns are provided, also, for

disengaging the variable motion drum from the starter shaft, whereby the engine may be cranked by hand when desired. Upon' release of the valve controlling means, the clutch members are disengaged and the drum is reset by suitable reti-active devices ready for the next operation.

For the purpose of clearly disclosing the invention to those skilled in the art, I have illustrated the same in the accompanying drawings.

Figure 1 is a diagrammatic view illustrating the starting device applied to a motor vehicle. Fig. 2 is an enlarged detail view, partly in section, showing the device adapted to be manually operated, as well as fluid operated. Fig. 3 is an enlarged sectional view through the control valve. Fig. 4 is a side elevation of a part of the valve and clutch operating lever. Fig. 5 is a detail view of the automatic clutch release member.

In the embodiment of the invention disclosed in the accompanying drawings, I have shown the starting mechanism mounted upon the frame of an ordinary motor vehicle, wherein the internal combustion engine is indicated at 10. The engine shaft 11 is provided with a clutch member 12 adapted to be engaged by another clutch member 13 carried by a starter shaft 14, positioned preferably in alinement with the engine shaft 11. The starter shaft 14 is suitably -mounted in the frame of the vehicle and is preferably provided with a spring 15, one end of which bears against the frame of the-vehicle, vwhile the other end may bear against a suitable collar or a part of a starting drum to maintain the clutch members 12 and 13 normally out of engagement with each other, whereby the rotation of the engine shaft 11 will not affect the starter shaft 14. Mounted on this starter shaft 14 is a drum 16, which I have termed herein as a variable motion drum. This drum is secured for rotation with the shaft 14 by a.

binding screw 16a. This drum is provided with a series of webs, at least one of which, 17a, is of greater diameter than the remaining webs, for a purpose to be hereinafter referred to. Coperating with the'drum 16 and shaft 14 is a lever 18 pivoted at 19 to the frame which is adapted to be operated by any suitable means, such as the flexible connection 20 extending from the lever 18 to a pull rod comprising sections 21a, 21D, which are connected with a foot lever 21,

which latter lever is adapted to be operated by the driver of the vehicle. The purpose of the lever 18 is to move the drum 16 and starter shaft 14 in the direction of the engine 10 to bring the clutch members l2 and 13 into operative engagement, when it is desired to start the engine b y means of the automatic device. This drum 16 is provided with a central member, which permits of the disengagement of the drum from the shaft 14, whereby the shaft 14 may be free to be turned by the ordinary hand-crank engaging its end 14, when it is desired to crank the engine by hand, in the event of the automatic cranking means getting out of order. When the hand crank is used, the screw 16 is loosened from engagement with the shaft 14. If desired, the flexible connection 20 may be provided with suitable resilient means, such as a spring 22, to cushion the movement of lever 18. This lever may be provided with a forked end to engage a part of the drum for moving the same, as will be readily understood.

Suitably mounted on the vehicle is a fluid tank, such as a compressed air tank, indicated at 23, leading from which is a pipe 24 to a. control valve 25. If desired, another valve may be placed in the pipe 24 between the tank 23 and valve 25 which is shown as a manually operated valve to control the supply of fluid in the tank. Extending from the valve 25 to a start-ing cylinder 27 is a pipe 28'adapted to convey fluid from the tank 23,.through the valve 25 and pipe 28, to the head of a piston 29 in cylinder 27. This piston 29 is adapted to move in the cylinder under pressure of the air, when admitted thereto through the valve 25, and operates to revolve the starter shaft in one direction by means of its piston rod 30 and flexible connection 0fL passing over the drum 16. This flexible connection is preferably wound first upon the members 17 of lesser diameter and inally over the member 17"L of greater diameter than said drum, thence around a suitable pulley 32 to the piston head 29. It will be understood, therefore, that the movement of the piston head 29 toward the end 33 of the cylinder 27 will rotate shaft 14 somewhat slowly at first and then increase the speed as the flexible connection 30a is being drawn from the members 17 to said drum.

The flexible connection 30 is rewound upon the drum by a suitable retracting element, shown in the drawings composed of a spring 34 mounted upon a suitable part of the frame having a flexible connection 35 which is shown extending over a pulley 36 and into engagement with the drum 16, wherebywhen the drum is rotated by the action of piston 29 the iexible connection 35 will be wound upon the drum to distend the spring 34 and store power therein. The release of pressure from the piston will permit the spring 34 to retract, and consequently revolve the drum in the opposite direction and windfthe cable 39a thereon.

An essential feature of the invention resides in the control valve 25 which is illustrated more clearly in Fig. 3. This valve is operated at substantially the same time as the lever 18, by the foot pedal 21, or by any other suitable means, under the control of the driver ofthe vehicle. The valve is shown provided with two cylinders 37, 38 each having a plurality of chambers 37a, 37", 38, 38". 1n the cylinder 37 is provided a spring-actuated plunger 39 having a stem 40, the upper end of which contacts with a lever 41, fulcrumed at 42 to a part ofthe casing connecting the cylinders 37, 38. The plunger 39 serves as a valve control for the passage of air from the tank 23 to cylinder 38, through a suitable port 43, air being admitted to said cylinder 37 through a port 44. The plunger 39 is maintained in its closed position by a suitable spring 45 which forces said plunger 39 against the valve seat 4G formed in said casing37.

Cylinder 38 is provided with a valve seat 47 adapted to be engaged by a valve 48, which is normally maintained in position by a suitable spring 49. The plunger 48 is provided with a plunger rod 50, contacting with the lever 41. This casing 38 is provided with a port 52 leading from said cylinder 38 to the starting cylinder 27 to admit air back of the piston After said piston 29 shall have performed its function, and to permit the drum 16 to be returned to its starting point by the retractive means .i

34, the valve 48 will then be opened to permit the air to be exhausted back of piston 29, back through port 52 of said casing 38, through the valve formed by the seat 47, and out through the exhaust port 53. The rocking of the lever 41, therefore, by an suitable means under the control of the driver, which also controls the operation of` the clutch, permits of the admission of air to the starting cylinder through said valve and the exhaust of air from the starting cylinder through the valve by merely releasing the control means of the starter.

To prevent damage to the engine, or to the drum, or the clutch members, there is provided a suitable trip, indicated at 54 in Fig. 4, which trip is connected to the drumactuating means 20 and to the foot pedal 21. The trip is more particularly illustrated in Fig. 5, wherein the connection 20 to the drum operating lever 18 is shown provided with a short lever 55 fulcrumed to a suitable part of the frame, shown at 56, which lever is provided with a pin 57 adapted to be engaged by a suitable hook member 58. A guide 59 is provided to maintain the hook member into operative relation with the lever 55. The hook 58 is provided with a stem 59 which preferably extends into a sleeve 60 having a suitable spring for impelling the hook 58 in the direction of the pin 57 of lever 55, and this sleeve may be provided with a stop 61, if desired, to limit the movement of the hook in a direction opposite to that caused by the spring 62. 'Io disengage the hook from the pin, there is provided suitable trip plates G3, one on the stem 59 and the other upon an adjacent portion of the frame, whereby when said trip plates 63 are permitted to ride one upon the other, the hook will be moved outwardly to a position to disengageits notch from the pin 57, thereby permitting spring 15 to automatically disengage members 12 and 13 of the clutch. This disengagement of the clutch is preferably so time that it will occur just before, or just as the air is admitted to the cylinder 29 and pressure is put upon the starter clutch. The air pressure, acting upon cylinder 29, and the consequent starting of the spiral drum will maintain the clutch members into position sufficiently long to give the clutch shaft 11 its necessary movement, after which the parts may be returned to their initial position, as will be readily understood from the foregoing description.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is 1. A starter for internal combustion engines comprising a starter shaft positioned adjacent to an engine shaft, a clutch cooperating with both of said shafts, means for storing fluid under pressure, a fluidactuated device for imparting rotary motion to the starter-shaft, a valve connecting the fluid storage means with the fluid actuated means, a lever and pull rod under the control of the operator which by movement in one direction operates the clutch and the valve and a trip device on said pull rod to disengage the clutch upon further movement of the lever in the same direction.

2. A starter for internal combustion engines comprising a starter-shaft positioned adjacent an engine shaft, a clutch operating with said shafts, a variable motion drum carried by the starter-shaft for imparting different speeds to the engine shaft, a valve for controlling the movement of the startershaft in one direction, a lever and pull rod; for operating the valve and clutch to impart movement to the engine shaft and means carried by said pull rod to automatically release the clutch before the lever reaches the limit of its valve operating movement.

3. In a starter for internal combustion engines, an engine shaft, a starter shaft positioned adjacent thereto, a clutch coperating with said shafts, fluid actuated means to rotate said starter shaft, a valve to control the passage of fluid to said fluid actuated means, an operating lever, and a pull rod mechanism connecting said lever with said valve and said starter shaft, said pull rod mechanism comprising a plurality of pull rod sections, means to connect said sections, and trip devices to disconnect said pull rod sections after the lever has been actuated to operate the clutch for the starter and engine shafts and said valve.

4. In a starter for internal combustion engines, a fluid pressure valve, an operating lever, a starter shaft, and pull rod mechanism extending from the operating lever to the starter shaft, said pull rod mechanism comprising a plurality of sections, one section having resilient connection with the starter shaft, and another section having detachable means to engage said first named section, said detachable section being provided with a catch, spring actuated means to direct the catch in the path of the firstl named section, and a trip device to disengage the catch from the first named section.

5. In a starter for internal combustion engines, an engine shaft, a starter shaft, means to maintain said shafts disengaged, means to store fluid under pressure, a cylinder having a fluid actuated piston, flexible means connecting the piston with said starter shaft, a valve positioned between and controlling the passage of fluid from the fluid storing means and said piston cylinder, said valve having a plurality of valve chambers for intaking or exhausting a fluid, each chamber being provided with a spring-actuated plunger, a rock lever connecting said plungers, and an operating lever connected to said valve rock lever and said starter shaft to simultaneously move said starter shaft into engagement with said engine shaft and to operate said valve to admit or exhaust fluid according to the position of the operating lever.

In testimony whereof, I affix my signature, in presence of two witnesses.

BIRGE IV. DAVENPORT. lllitnesses D. B. LYNCH, N. M. LYNCH.

Copies ot thll patent may h obtained for ive cent: each, by addressing the "Comninioner ot latenti,

Wallington, D. G." f 

